Jewels of Accord
The Jewels of Accord are a pair of jewels, one red and one white, that act as love charms. If two people each carry a jewel then those two people will fall in love. The Jewels of Accord play an important role in Hirukowashi-hen, as Rena Ryuuguu accidently swallows the red jewel and falls in love with many people as a result; including Jirou Tomitake, Miyo Takano, Kuraudo Ooishi, and Kyousuke Irie.
The Onigari-no-Ryūō (鬼狩柳桜, lit. demon-hunting willow cherry) is an ancient sword sealed within the Furude Shrine. It is said have once been used to slay a demon lord.
The Sonozaki handbell is a small handbell that is held by the head of the Sonozaki family. The location of the handbell is known only to the head and is passed down alongside the headship. The handbell only appears in the manga-only side story Yoigoshi-hen.